dpb wrote:
Yard Guy wrote:
...

What's the verdict on these things? Are they effective?

I've seen no independent testing results that indicated they're more
effective than alternatives tested--which is pretty much why they're
not particularly widespread; it appears that most of the glowing
testimonials are either sponsored "research" (read advertising hype)
or self-justification of the $$ spent to avoid admitting have been
suckered.
It's been a while since I looked but google found several studies a
while back from various land-grant universities, etc., that concluded
they're of minimal help if any...

That can only be because some werent that well designed.

Its been known for a long time now what attracts mosquitos.